This invention relates to a cool-wrought pressing forming method for slotted headless screws, particularly to one enhancing effectively production of tidy looking slotted headless screws and lowering their cost.
A conventional processing method for slotted headless screws includes various steps of pressing a material, forming a slot on an upper end surface and of cutting threads by a thread-forming machine. However, this kind of processing for slotted headless screws may cause hairy sides and an untidy circumference around a slot, damaged threads, etc. Moreover, cutting tools may also wear off, resulting in increased production cost and impossibility of enhancing the quality of products.
This invention has been devised to offer a cool-wrought pressing forming method for slotted headless screws, which can elevate effectively production of neat and tidy looking slotted headless screws with lowered cost.
The cool-wrought pressing forming method for slotted headless screws in the invention includes a plurality of stages, which have a first one of cutting linear material into a length of one screw material and pressing each screw material in five different molds and pressed by five different heads one by one orderly and to form an unfinished screw with a slot and then it is cut with threads by means of a thread forming machine to finish it. Then the slot of each finished screw is neat and tidy looking.